Bar codes are machine readable markings that encode and store data in a geometric pattern.
One-dimensional bar codes, such as the well-known Universal Price Code (UPC), encode and store data in a pattern of alternating black and white bars of different widths. See, FIG. 1. A start pattern is embedded at one end of the bar code, and a stop pattern is embedded at the opposite end of the bar code. The start/stop patterns allow the bar code scanner to identify the starting and ending points of the bar code as well as discern the central portion of the bar code containing the encoded data of interest.
The need to store larger amounts of data has led to the creation of two-dimensional bar codes. In one embodiment of a two-dimensional bar code, multiple rows of one-dimensional bar codes are provided. Another embodiment of a two dimensional bar code utilizes a matrix of black and white dots or squares arranged in a pattern. Examples of such a two-dimensional bar code include the well-known QR code and Data Matrix code. See, FIGS. 2A-2D. Indexing indicia are incorporated in the two-dimensional bar code to assist in the determination of code orientation as well as identify start and stop locations of the encoded data.
There are a number of concerns with the use of two-dimensional bar codes. One concern is the difficulty in decoding. Because the decoding operation uses an optical recognition based on a scan line approach, there are increased instances of failure to recognize the bar code due to rotation and perspective adjustments. This is especially a concern in the current market environment where consumers are increasingly using the camera function of their cellular telephones to take images of bar codes.
Another concern is aesthetic presentation. In many applications, the utilitarian appearance of the bar code is of no consequence, such as when used on a hang tag for or on the packaging of goods. However, bar codes are increasingly being used in advertising and other promotional materials (for example, to link to other content such as a website), and in this context the utilitarian appearance of the bar code may be distracting and unattractive. Designers are going to great lengths to graphically integrate the bar code in a more attractive aesthetic presentation within such advertising and promotional materials, but this can be difficult and no matter what integration steps are taken, the utilitarian appearance of the bar code is still present. Indeed, this concern is even more prevalent in situations where the overall image occupies a relatively small area, with the bar code occupying a disproportionate area and thus being even more distracting.
There is a need in the art to provide for a more attractive-looking two-dimensional bar code that is easy to decode.